Name that Ware February 2014

The Ware for February 2014 is shown below.

This month’s ware is a handsome bit of retro-computing contributed by Edouard Lafargue (ed _at_ aerodynes.org). The ware was a gift to him from his father.

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I don’t know, the look of it doesn’t seem to fit in with any of the other logic cards I can find. It seems like it might be taken from the DDP-116 form factor, but with smaller transistors, higher quality construction, etc. I’m going to take a long shot guess and go with mariner probe.

Could it have been a newer-generation DDP-116 card? Two unusual features, the transistor cases are TO-18s rather than the TO-5’s that you usually see, and there are a pile of jumpers for configuration that aren’t normal for these cards.

Agree. Seems to be 6 RS flip flops with connections between them. Refer to http://www.computerhistory.org/collections/catalog/102688848 , which also seems to be 6 RS flip flops.
Both have very similar circular QC stamps in the center of the component side.
“3468” stamp at top could be date code 34th week of 1968.

Yep. Given the discrete transistors, I’d place it from early to mid ’60s. Most of the calculators of that era had fairly large boards (purpose built for the task), whereas computers were more likely to use smaller generic modules like this to build up the system. Another possibility is military (missile guidance system, etc.).

The module is marked “FL-36,” which follows the two-letter, two-digit pattern for model numbers of Honeywell/3C S-PAC digital modules, though I didn’t find that model listed in the two instruction manuals posted here:

The 3 terminal PROFILE components do not seem to be ceramic caps that I have ever encountered. The 2 terminals close together do not seem to be internally “shorted” in the component. In many cases, the end terminal goes to the PCB connector without any other components involved. The middle terminal goes to transistor bases or offboard via a resistor. Could they be tapped metal film resistors, or even a tapped inductors?

Not sure but Bunnie seems to have decided that my suggestion that this came from the Apollo space program should not be published? Yes I accidently posted it twice because I did not notice that it would only be displayed after moderation…

The 3C logo gives something away: Computer Control Company. It can be found on Wikipedia. It was sold to Honeywell in 1966 (according to wikipedia) and the products discontinued in 1970. Which matches with the 3468 code stamped on the board (week 34, 1968?). 3C made indeed the DDP series.

If this board is indeed made in 1968, this board is likely a spare part or continued production of an older model. Maybe a DDP-19 board.

That leaves the DDP 19: http://www.ddp116.org/products/ddp19/ddp19.jpg . This would be older than 1968. It might an older product still be in production at that time, might be a spare part, or perhaps an aircraft/space/military product manufactured to an older (conservative) spec.

This is an S-PAC modular logic card produced by Computer Control Company (“3C”) using pre-IC discrete electronics. [1]

Complex digital circuits could be constructed by inserting a row of different S-PACs into an S-BLOC enclosure. 3C actually entered the minicomputer business by building the DDP-116 and DDP-24/224 out of of S-BLOCs. [2][3]

These parts wouldn’t have flown in space, though they were widely used at NASA (DDP-224s powered mission simulators for Gemini and Apollo as well as a full instruction set simulator of the Apollo Guidance Computer). [4]

The abundance of big caps on this particular S-PAC is seems unusual, and the design doesn’t resemble anything in the catalogs of 1-megacycle S-PACs. [5] Maybe some kind of register file?

Looks like a dual high frequency operational amplifier from an analog computer. (Symmetry around the central axis as well as all traces are curved.) The blade end connectors are very different coming out at a right angles to the board. Are they there to cut down on induced harmonics in the backplane, to provide low noise connections, or meant to be used in a high vibration environment??

Whatever this is – it is absolutely beautiful – almost has a bit of a steampunkish appeal. SOT-23 transistors and 0603 chip resistors and auto-routed traces are so ugly compared to this utter work of art. I just wonder if something like this could be pulled off with a new line of SMD components that would be created to look good instead of just doing the job while taking as little pcb real estate as possible.
But I digress.

I like especially the jumpers A-B-C D-E-F H-J-K and the cute little bends in the diodes’ leads.

Others have already pointed out the symmetry which actually is almost a double symmetry, so 4 vertical (on the big image) blocks.

When overlaying front and back you can see that the 4 big red capacitors in the middle “PROFILE” connect as only component to one leg of a capacitor each – very strange, a transistor circuit where either base, emitter or collector is kept on a floating dc level? Oh no, now I see – the big capacitors have three pins – most probably the two outer pins go to the inner plate on the inside of the ceramics tube and are thus connected. Cool using a component as a jumper at the same time!

For speculations about 8 latches or flipflops – no the transistor pairs are not connected consistently over the board.

Everyone is saying that it’s a card used in some serious vintage tech. Just to be different, I am going to guess that it is actually an Ion Generator (AKA Ozone Generator). That’s why there are so many pins; that’s where the ions are released.

FL-36 does indeed seem to fit the pattern for naming Honeywell/3C S-PAC modules but it doesn’t appear in either of the catalogues I could find. My wild guess is something to do with clock distribution ( (F for frequency? L for locking? Latching? Looping?).